ELECTROSTATIC ION THRUSTERS - TOWARDS PREDICTIVE MODELING

For satellite missions, thrusters have to be qualified in large vacuum vessels to simulate space environment. One caveat of these experiments is the possible modification of the beam properties due to the interaction of the energetic ions with the vessel walls. Impinging ions can produce sputtered impurities or secondary electrons from the wall. These can stream back into the acceleration channel of the thruster and produce co-deposited layers. Over the long operation time of thousands of hours, such layers can modify the optimized geometry and induce changes of the ion beam properties, e.g. broadening of the angular distribution and thrust reduction. To study such effects, a Monte Carlo code for the simulation of the interaction of ion thruster beams with vessel walls was developed. Strategies to overcome sputter limitations by additional baffles are studied with the help of this Monte-Carlo erosion code.<br /><br />

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A 3D particle model for the plume CEX simulation

The Aeronautical Journal ◽

10.1017/aer.2018.79 ◽

2018 ◽

Vol 122 (1255) ◽

pp. 1425-1441 ◽

Cited By ~ 1

Author(s):

C. Lu ◽

P. Qiu ◽

Y. Cao ◽

T.P. Zhang ◽

J.J. Chen

Keyword(s):

Monte Carlo ◽

Analytical Model ◽

Ion Beam ◽

Direct Simulation Monte Carlo ◽

Particle Model ◽

Neutral Atoms ◽

Ion Thruster ◽

Technology Application ◽

Particle In Cell ◽

Ion Thrusters

ABSTRACTCharge Exchange (CEX) ion is the main factor causing the plume pollution. The distribution of CEX ions is determined by the distribution of beam ions and neutral atoms. Hence, the primary problem in the study of the plume is how to accurately simulate the distribution of beam ions and neutral atoms. At present, the most commonly used model utilised for the plume simulation is the analytical model proposed by Roy for the plume simulation of the NASA Solar Technology Application Readiness (NSTAR) ion thruster. However, this analytical model can only be applied to the ion beam with small divergence angles. In addition, the analytical model is no longer applicable to the simulation for the plume of a new type of ion thruster that appeared recently, which is called the annular ion thruster. In this paper, a 3D particle model is proposed for the plume simulation of ion thrusters consisting of the particle model for beam ions, the Direct Simulation Monte Carlo (DSMC) model for neutral atoms and the Immersed Finite Element-Particle In Cell-Monte Carlo Collision (IFE-PIC-MCC) model for CEX ions. Then, the plume of the NSTAR ion thruster is simulated by both Roy's model and the 3D particle model. The simulation results of both models are then compared with the experimental results. It is shown that the numerical results of the 3D particle model agree well with those of the analytical model and the experimental data. And this 3D particle model can also be used for other electric thrusters.

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Ion beam transport in tissue-like media using the Monte Carlo code SHIELD-HIT

Physics in Medicine and Biology ◽

10.1088/0031-9155/49/10/008 ◽

2004 ◽

Vol 49 (10) ◽

pp. 1933-1958 ◽

Cited By ~ 96

Author(s):

Irena Gudowska ◽

Nikolai Sobolevsky ◽

Pedro Andreo ◽

D evad Belki ◽

Anders Brahme

Keyword(s):

Monte Carlo ◽

Ion Beam ◽

Monte Carlo Code ◽

Beam Transport

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SU-E-T-323: The FLUKA Monte Carlo Code in Ion Beam Therapy

Medical Physics ◽

10.1118/1.4888656 ◽

2014 ◽

Vol 41 (6Part16) ◽

pp. 298-298 ◽

Cited By ~ 2

Author(s):

I Rinaldi ◽

Keyword(s):

Monte Carlo ◽

Ion Beam ◽

Monte Carlo Code ◽

Ion Beam Therapy

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Performance of a rf neutralizer operating with noble gases and iodine

The European Physical Journal Applied Physics ◽

10.1051/epjap/2020190213 ◽

2020 ◽

Vol 91 (1) ◽

pp. 10901 ◽

Cited By ~ 1

Author(s):

Patrick Dietz ◽

Felix Becker ◽

Konstantin Keil ◽

Kristof Holste ◽

Peter J. Klar

Keyword(s):

Ion Beam ◽

Experimental Studies ◽

Space Mission ◽

Inert Gases ◽

Rf Discharge ◽

Global Modeling ◽

Ion Thruster ◽

Hollow Cathodes ◽

Inductively Coupled ◽

Ion Thrusters

Neutralization of the extracted ion beam is a mandatory task for any ion thruster based space mission. The required lifetimes are in the order of ten thousand hours. This requirement is fulfilled by hollow cathodes operating with xenon, but has not been demonstrated for operation with iodine yet. Furthermore, the power consumption as well as the demand on mass flow should be kept as low as possible. Since the halogen iodine seems to be a viable alternative to xenon for operating ion thrusters, a suitable neutralizer concept that can operate with the corrosive gas for the time periods stated above is required. We propose to use a neutralizer based on an inductively coupled rf discharge as alternative to hollow cathodes. We studied the performance of a prototypical neutralizer operating with iodine as well as the inert gases xenon and krypton and compared the experimental studies with the results of global modeling.

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